Dynamic leg-motion and its effect on the aerodynamic performance of cyclists

Timothy N. Crouch, David Burton, Mark C. Thompson, Nicholas A.T. Brown, John Sheridan

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

In this wind-tunnel based experimental study, the flow topology of the near wake of a generic anatomically accurate model cyclist is mapped for a range of reduced pedalling frequencies. Wake flow fields for both static leg and pedalling cyclists are compared over the full 360° rotation of the crank using both time- and phase-averaging. The primary wake flow structures and aerodynamic forces are quantified and analysed under dynamic pedalling conditions representative of an elite-level time-trial cyclist. Over the range of reduced pedalling frequencies studied, only minor variation was detected between the instantaneous drag and primary vortical structures of a pedalling cyclist compared to a stationary cyclist with the pedals in the same position. A simplified model of the aerodynamic forces acting on the legs under motion is presented to provide insight into how the motion of the legs influences aerodynamic drag. A comparison of predicted forces from this model with those from experiments provides a new perspective on how the aerodynamics of cyclists may be optimised.

Original languageEnglish
Pages (from-to)121-137
Number of pages17
JournalJournal of Fluids and Structures
Volume65
DOIs
Publication statusPublished - 1 Aug 2016
Externally publishedYes

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Aerodynamics
Aerodynamic drag
Flow structure
Wind tunnels
Drag
Flow fields
Topology
Experiments

Cite this

Crouch, Timothy N. ; Burton, David ; Thompson, Mark C. ; Brown, Nicholas A.T. ; Sheridan, John. / Dynamic leg-motion and its effect on the aerodynamic performance of cyclists. In: Journal of Fluids and Structures. 2016 ; Vol. 65. pp. 121-137.
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Dynamic leg-motion and its effect on the aerodynamic performance of cyclists. / Crouch, Timothy N.; Burton, David; Thompson, Mark C.; Brown, Nicholas A.T.; Sheridan, John.

In: Journal of Fluids and Structures, Vol. 65, 01.08.2016, p. 121-137.

Research output: Contribution to journalArticle

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